CN114740595B - Optical lens, camera module and electronic equipment - Google Patents

Abstract

The invention discloses an optical lens, a camera module and electronic equipment. The optical lens includes: a first lens with refractive power arranged sequentially along the optical axis from the object side to the image side; are convex and concave respectively; the second lens with positive refractive power, its image side is convex at the near optical axis; the third lens with negative refractive power, its object side and image side are respectively concave at the near optical axis and a convex surface; a fourth lens with positive refractive power, whose object side is convex at the near optical axis, and the first lens to the fourth lens include at least one aspherical lens. The optical lens, camera module and electronic equipment provided by the present invention can meet the design requirement of miniaturization while realizing high imaging quality.

Description

Optical lenses, camera modules and electronic equipment

Technical Field

The present invention relates to the field of optical imaging technology, and in particular to an optical lens, a camera module and an electronic device.

Background Art

With the advancement and development of technology, people have higher and higher requirements on the camera capabilities of electronic devices. At the same time, electronic devices on the market show a trend of miniaturization, which requires that the lens must not only meet the imaging quality, but also take into account the miniaturization design, so as to save space for other components.

Therefore, how to configure the number of lenses, surface shape and other parameters of the optical lens so that the lens can take into account the characteristics of miniaturization and imaging quality at the same time has become a problem that needs to be solved urgently.

Summary of the invention

The embodiments of the present invention disclose an optical lens, a camera module and an electronic device, which can achieve high imaging quality while meeting the design requirements of miniaturization.

In order to achieve the above-mentioned object, in a first aspect, the present invention discloses an optical lens, wherein the optical lens comprises, in order from the object side to the image side along the optical axis:

A first lens having refractive power, wherein the object side surface of the first lens is convex at the near optical axis, and the image side surface of the first lens is concave at the near optical axis;

A second lens element having positive refractive power, wherein the image side surface of the second lens element is convex at the near optical axis;

A third lens having negative refractive power, wherein the object side surface of the third lens is concave at the near optical axis, and the image side surface of the third lens is convex at the near optical axis;

The fourth lens has positive refractive power, the object side surface of the fourth lens is convex at the near optical axis, and the first lens to the fourth lens include at least one aspherical lens.

By limiting the object side surface and image side surface of the first lens of the optical lens to be convex and concave at the near optical axis respectively, incident light at a large angle can enter the optical lens, expanding the field of view angle range of the optical lens to obtain the characteristics of a large field of view angle, and at the same time, the incident light can be effectively converged, which is conducive to controlling the size of the first lens in the direction perpendicular to the optical axis, ensuring that the first lens has a smaller aperture to meet the design of miniaturization of the optical lens; when the light enters the second lens with positive refractive power, combined with the surface design of the image side surface of the second lens being convex at the near optical axis, it is conducive to correcting the aberration generated by the incident light through the first lens, so as to improve the imaging resolution of the optical lens, thereby improving the imaging quality of the optical lens; in combination with the third lens with negative refractive power, and the third The object side surface and image side surface of the lens are concave and convex respectively at the near optical axis, which is conducive to converging the incident light and reducing the deflection angle of the light. At the same time, the object side surface and image side surface of the third lens are concave and convex respectively at the near optical axis, which can reduce the total length of the optical lens and is conducive to the miniaturization of the optical lens. When the light enters the fourth lens with positive refractive power, combined with the setting that the object side surface of the fourth lens is convex at the near optical axis, the marginal field light can be effectively converged to correct the marginal field aberration of the front lens group, and it is also conducive to the convergence of light, thereby reducing the incident angle of the light on the imaging plane, so as to reduce the sensitivity of the optical lens and improve the imaging quality of the optical lens. At the same time, it can also effectively shorten the total length of the optical lens and realize the miniaturization of the optical lens.

As an optional implementation manner, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relationship:

0.4<|f12/f34|<0.8;

Wherein, f12 is the combined focal length of the first lens and the second lens, and f34 is the combined focal length of the third lens and the fourth lens.

By rationally configuring the ratio of the combined focal length of the first lens and the second lens to the combined focal length of the third lens and the fourth lens, the aberration of the optical lens can be balanced, the edge light can be effectively converged, and at the same time the compactness of the optical lens can be ensured, which is conducive to reducing the size of the optical lens and realizing a miniaturized design.

As an optional implementation manner, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relationship:

3<|f2/SAG22|<6;

Among them, f2 is the focal length of the second lens, and SAG22 is the distance from the maximum effective aperture of the image side surface of the second lens to the intersection of the image side surface of the second lens and the optical axis in the direction of the optical axis (that is, the sagittal height of the image side surface of the second lens at the maximum effective radius).

By constraining the ratio of the focal length of the second lens to the sagittal height of the image side surface of the second lens at the maximum effective radius, the chromatic aberration and spherical aberration of the optical lens can be minimized, thereby improving the imaging quality of the optical lens, and at the same time, the edge field of view light can be effectively converged to correct the edge field of view aberration and improve the imaging quality of the optical lens. In addition, by controlling the sagittal height of the image side surface of the second lens at the maximum effective radius, the surface complexity of the second lens can be reduced and the processability of the second lens can be improved.

As an optional implementation manner, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relationship:

1<|f4/SAG41|<3;

Among them, f4 is the focal length of the fourth lens, SAG41 is the distance from the maximum effective aperture of the object side surface of the fourth lens to the intersection of the object side surface of the fourth lens and the optical axis in the direction of the optical axis (that is, the sagittal height of the object side surface of the fourth lens at the maximum effective radius).

By constraining the ratio of the focal length of the fourth lens to the sagitta of the object side of the fourth lens at the maximum effective radius, the chromatic aberration and spherical aberration of the optical lens can be reduced, thereby improving the imaging quality of the optical lens. At the same time, by controlling the focal length of the fourth lens, the refractive power of the fourth lens can be reasonably configured to enhance the light collecting ability of the optical lens, so that the main light maintains a sufficiently small exit angle, thereby improving the relative illumination of the optical lens, so as to improve the imaging quality of the optical lens. In addition, by controlling the sagitta of the object side of the fourth lens at the maximum effective radius, the surface complexity of the fourth lens can be reduced and the processability of the fourth lens can be improved.

As an optional implementation manner, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relationship:

|SAG22/SAG41|<1.2;

Among them, SAG22 is the distance from the maximum effective aperture of the image side surface of the second lens to the intersection of the image side surface of the second lens and the optical axis in the direction of the optical axis (that is, the sagittal height of the image side surface of the second lens at the maximum effective radius), and SAG41 is the distance from the maximum effective aperture of the object side surface of the fourth lens to the intersection of the object side surface of the fourth lens and the optical axis in the direction of the optical axis (that is, the sagittal height of the object side surface of the fourth lens at the maximum effective radius).

By limiting the ratio of the sagitta of the image side surface of the second lens at the maximum effective radius to the sagitta of the object side surface of the fourth lens at the maximum effective radius, the curvature of the second lens and the fourth lens can be limited, thereby balancing the large spherical aberration produced by the optical lens, promoting the aberration balance of the optical lens, and improving the overall resolution of the optical lens, thereby improving the imaging quality of the optical lens. At the same time, by controlling the sagitta of the second lens and the fourth lens at the maximum effective radius, it is beneficial to compress the size of the optical lens to meet the miniaturization of the optical lens.

As an optional implementation manner, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relationship:

(|SAG41|+|SAG42|)/CT4<1;

Among them, SAG41 is the distance from the maximum effective aperture of the object side surface of the fourth lens to the intersection of the object side surface of the fourth lens and the optical axis in the direction of the optical axis (that is, the sagittal height of the object side surface of the fourth lens at the maximum effective radius), SAG42 is the distance from the maximum effective aperture of the image side surface of the fourth lens to the intersection of the image side surface of the fourth lens and the optical axis in the direction of the optical axis (that is, the sagittal height of the image side surface of the fourth lens at the maximum effective radius), and CT4 is the thickness of the fourth lens on the optical axis (that is, the center thickness of the fourth lens).

By constraining the above relationship, the refractive power and thickness of the fourth lens can be reasonably controlled to avoid the fourth lens being too thin or too thick, which is beneficial to keeping the exit angle of the main light small enough, thereby reducing the incident angle of the light on the imaging surface, thereby reducing the sensitivity of the optical lens and improving the imaging quality of the optical lens.

As an optional implementation manner, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relationship:

1<|(R41-R42)/(R41+R42)|<1.5;

Wherein, R41 is the curvature radius of the object side surface of the fourth lens at the optical axis, and R42 is the curvature radius of the image side surface of the fourth lens at the optical axis.

By limiting the ratio of the curvature radius of the object side surface to the image side surface of the fourth lens, the curvature degree and thickness ratio trend of the object side surface and the image side surface of the fourth lens can be effectively controlled to limit the shape change of the fourth lens. In this way, the spherical aberration contribution of the fourth lens can be controlled within a reasonable range, thereby effectively improving the aberration of the optical lens and enhancing the imaging quality of the optical lens; at the same time, it is also beneficial to reduce the surface complexity of the fourth lens and improve the processability of the fourth lens, thereby ensuring the imaging quality of the optical lens.

As an optional implementation manner, in an embodiment of the first aspect of the present invention, the optical lens satisfies the following relationship:

|(R31-R32)/(R31+R32)|<0.5; and/or, 2<|f/f2+f/f4|<3;

Among them, R31 is the curvature radius of the object side of the third lens at the optical axis, R32 is the curvature radius of the image side of the third lens at the optical axis, f is the focal length of the optical lens, f2 is the focal length of the second lens, and f4 is the focal length of the fourth lens.

By reasonably configuring the curvature radii of the object side and the image side of the third lens, the curvature of the third lens can be effectively controlled, making the lens shape of the third lens smooth and uniform, thereby reducing the assembly sensitivity of the optical lens. At the same time, the overall imaging quality from the center to the edge of the imaging surface is clear and uniform, which can effectively reduce the risk of ghost images, enhance the resolution capability of the optical lens, and thus improve the imaging quality of the optical lens.

In addition, by properly configuring the focal length of the optical lens and the focal lengths of the second lens and the fourth lens, the large spherical aberration produced by the optical lens can be balanced, the overall resolution of the optical lens can be improved, and the edge aberration of the optical lens can be corrected to improve the imaging quality of the optical lens. At the same time, by controlling the focal length of the optical lens, the total length of the optical lens can be compressed, thereby facilitating the miniaturization design of the optical lens.

In a second aspect, the present invention discloses a camera module, the camera module comprising an image sensor and the optical lens as described in the first aspect, wherein the image sensor is arranged on the image side of the optical lens. The camera module with the optical lens can achieve high imaging quality while also meeting the design requirements of miniaturization.

In a third aspect, the present invention discloses an electronic device, comprising a housing and a camera module as described in the second aspect, wherein the camera module is disposed in the housing. The electronic device having the camera module can achieve high imaging quality while also meeting the design requirements of miniaturization.

Compared with the prior art, the beneficial effects of the present invention are as follows: an optical lens, a camera module and an electronic device provided by the embodiments of the present invention, the object side surface and the image side surface of the first lens of the optical lens are convex and concave respectively at the near optical axis, so that incident light at a large angle can enter the optical lens, expand the field of view angle range of the optical lens, so as to obtain the characteristics of a large field of view angle, and at the same time, the incident light can be effectively converged, which is conducive to controlling the size of the first lens in the direction perpendicular to the optical axis, ensuring that the first lens has a smaller aperture to meet the design of miniaturization of the optical lens; when the light enters the second lens with positive refractive power, combined with the surface design that the image side surface of the second lens is convex at the near optical axis, it is conducive to correcting the aberration generated by the incident light through the first lens, so as to improve the imaging resolution of the optical lens, thereby improving the cost of the optical lens. image quality; cooperate with the third lens with negative refractive power, and the object side surface and image side surface of the third lens are concave and convex respectively at the near optical axis, which is conducive to converging the incident light and reducing the deflection angle of the light. At the same time, the object side surface and image side surface of the third lens are concave and convex respectively at the near optical axis, which can reduce the total length of the optical lens and is conducive to the miniaturization of the optical lens; when the light enters the fourth lens with positive refractive power, cooperate with the setting that the object side surface of the fourth lens is convex at the near optical axis, it can effectively converge the marginal field light to correct the marginal field aberration of the front lens group, and it can also be conducive to the convergence of light, thereby reducing the incident angle of light on the imaging plane, so as to reduce the sensitivity of the optical lens and improve the imaging quality of the optical lens. At the same time, it can also effectively shorten the total length of the optical lens and realize the miniaturization of the optical lens.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic diagram of the structure of an optical lens disclosed in the first embodiment of the present application;

FIG2 is a longitudinal spherical aberration diagram (mm), an astigmatism curve diagram (mm), and a distortion curve diagram (%) of the optical lens disclosed in the first embodiment of the present application;

FIG3 is a schematic diagram of the structure of an optical lens disclosed in a second embodiment of the present application;

FIG4 is a longitudinal spherical aberration diagram (mm), an astigmatism curve diagram (mm), and a distortion curve diagram (%) of the optical lens disclosed in the second embodiment of the present application;

FIG5 is a schematic diagram of the structure of an optical lens disclosed in a third embodiment of the present application;

6 is a longitudinal spherical aberration diagram (mm), an astigmatism curve diagram (mm), and a distortion curve diagram (%) of the optical lens disclosed in the third embodiment of the present application;

FIG7 is a schematic diagram of the structure of an optical lens disclosed in a fourth embodiment of the present application;

FIG8 is a longitudinal spherical aberration diagram (mm), an astigmatism curve diagram (mm), and a distortion curve diagram (%) of the optical lens disclosed in the fourth embodiment of the present application;

FIG9 is a schematic structural diagram of an optical lens disclosed in a fifth embodiment of the present application;

FIG10 is a diagram of longitudinal spherical aberration (mm), astigmatism curve (mm), and distortion curve (%) of the optical lens disclosed in the fifth embodiment of the present application;

FIG11 is a schematic structural diagram of a camera module disclosed in the present application;

FIG. 12 is a schematic diagram of the structure of the electronic device disclosed in the present application.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

In the present invention, the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like are based on the directions or positional relationships shown in the drawings. These terms are mainly used to better describe the present invention and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific direction, or to be constructed and operated in a specific direction.

In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those skilled in the art, the specific meanings of these terms in the present invention can be understood according to specific circumstances.

In addition, the terms "installed", "set", "provided with", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, "plurality" means two or more.

The technical solution of the present invention will be further described below in conjunction with embodiments and drawings.

Please refer to FIG. 1 . According to the first aspect of the present application, the present application discloses an optical lens 100, which includes a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4, which are sequentially arranged from the object side to the image side along the optical axis O. During imaging, light enters the first lens L1, the second lens L2, the third lens L3, and the fourth lens L4 sequentially from the object side of the first lens L1, and is finally imaged on the imaging surface 101 of the optical lens 100. Among them, the first lens L1 has positive refractive power or negative refractive power, the second lens L2 has positive refractive power, the third lens L3 has negative refractive power, and the fourth lens L4 has positive refractive power.

Furthermore, the object-side surface 11 of the first lens L1 is convex at the near optical axis O, and the image-side surface 12 of the first lens L1 is concave at the near optical axis O; the object-side surface 21 of the second lens L2 is convex or concave at the near optical axis O, and the image-side surface 22 of the second lens L2 is convex at the near optical axis O; the object-side surface 31 of the third lens L3 is concave at the near optical axis O, and the image-side surface 32 of the third lens L3 is convex at the near optical axis O; the object-side surface 41 of the fourth lens L4 is convex at the near optical axis O, and the image-side surface 42 of the fourth lens L4 is convex or concave at the near optical axis O.

By properly configuring the surface shapes and refractive powers of the lenses between the first lens L1 to the fourth lens L4, the optical lens 100 can achieve high imaging quality while meeting the design requirements of miniaturization.

Furthermore, in some embodiments, the materials of the first lens L1, the second lens L2, the third lens L3 and the fourth lens L4 are all plastic, in which case the optical lens 100 can reduce weight and reduce costs. In other embodiments, the materials of the first lens L1, the second lens L2, the third lens L3 and the fourth lens L4 can also be glass, in which case the optical lens 100 can have a good optical effect and can also reduce the temperature sensitivity of the optical lens 100.

In some embodiments, in order to facilitate processing and molding, the first lens L1, the second lens L2, the third lens L3 and the fourth lens L4 can all be aspherical lenses. It can be understood that in other embodiments, the first lens L1, the second lens L2, the third lens L3 and the fourth lens L4 can also be spherical lenses.

In some embodiments, the optical lens 100 further includes a stop STO, which may be an aperture stop and/or a field stop. For example, the stop STO may be an aperture stop, or the stop STO may be a field stop, or the stop STO may be an aperture stop and a field stop. The stop STO may be disposed between the image side surface 12 of the first lens L1 and the object side surface 21 of the second lens L2, so that the exit pupil can be moved away from the imaging surface 101, and the effective diameter of the optical lens 100 can be reduced without reducing the telecentricity of the optical lens 100, thereby achieving miniaturization. It is understandable that in other embodiments, the stop STO may also be disposed between other lenses, and the setting may be adjusted according to actual conditions, and this embodiment does not specifically limit this.

In some embodiments, the optical lens 100 further includes an infrared filter 50, and the infrared filter 50 is disposed between the fourth lens L4 and the imaging surface 101 of the optical lens 100. The infrared filter 50 is selected to filter out infrared light, so that the imaging is more in line with the visual experience of the human eye, thereby improving the imaging quality. It is understandable that the infrared filter 50 can be made of optical glass coating, or can be made of colored glass, or an infrared filter 50 of other materials, which can be selected according to actual needs and is not specifically limited in this embodiment.

In some embodiments, the optical lens 100 satisfies the following relationship:

0.4<|f12/f34|<0.8;

Wherein, f12 is the combined focal length of the first lens L1 and the second lens L2, and f34 is the combined focal length of the third lens L3 and the fourth lens L4.

By reasonably configuring the ratio of the combined focal length of the first lens L1 and the second lens L2 to the combined focal length of the third lens L3 and the fourth lens L4, the aberration of the optical lens 100 can be balanced, the edge light can be effectively converged, and the compactness of the optical lens 100 can be ensured, which is conducive to reducing the size of the optical lens 100 and realizing a miniaturized design.

In some embodiments, the optical lens 100 satisfies the following relationship:

3<|f2/SAG22|<6;

Wherein, f2 is the focal length of the second lens L2, SAG22 is the distance from the maximum effective aperture of the image side surface 22 of the second lens L2 to the intersection of the image side surface 22 of the second lens L2 and the optical axis O in the direction of the optical axis O (i.e., the sagittal height of the image side surface 22 of the second lens L2 at the maximum effective radius).

By constraining the ratio of the focal length of the second lens L2 to the sagittal height of the image side surface 22 of the second lens L2 at the maximum effective radius, the chromatic aberration and spherical aberration of the optical lens 100 can be minimized, thereby improving the imaging quality of the optical lens 100, and at the same time, the edge field of view light can be effectively converged to correct the edge field of view aberration, thereby improving the imaging quality of the optical lens 100. In addition, by controlling the sagittal height of the image side surface 22 of the second lens L2 at the maximum effective radius, the surface complexity of the second lens L2 can be reduced, and the processability of the second lens L2 can be improved.

In some embodiments, the optical lens 100 satisfies the following relationship:

1<|f4/SAG41|<3;

Wherein, f4 is the focal length of the fourth lens L4, SAG41 is the distance from the maximum effective aperture of the object side surface 41 of the fourth lens L4 to the intersection of the object side surface 41 of the fourth lens L4 and the optical axis O in the direction of the optical axis O (i.e., the sagittal height of the object side surface 41 of the fourth lens L4 at the maximum effective radius).

By constraining the ratio of the focal length of the fourth lens L4 to the sagittal height of the object side surface 41 of the fourth lens L4 at the maximum effective radius, the chromatic aberration and spherical aberration of the optical lens 100 can be reduced, thereby improving the imaging quality of the optical lens 100. At the same time, by controlling the focal length of the fourth lens L4, the refractive power of the fourth lens L4 can be reasonably configured to enhance the light collecting ability of the optical lens 100, so that the main light maintains a sufficiently small exit angle, thereby improving the relative illumination of the optical lens 100, so as to improve the imaging quality of the optical lens 100. In addition, by controlling the sagittal height of the object side surface 41 of the fourth lens L4 at the maximum effective radius, the surface complexity of the fourth lens L4 can be reduced, and the processability of the fourth lens L4 can be improved.

In some embodiments, the optical lens 100 satisfies the following relationship:

|SAG22/SAG41|<1.2;

Wherein, SAG22 is the distance from the maximum effective aperture of the image side surface 22 of the second lens L2 to the intersection of the image side surface 22 of the second lens L2 and the optical axis O in the direction of the optical axis O (i.e., the sag height of the image side surface 22 of the second lens L2 at the maximum effective radius), and SAG41 is the distance from the maximum effective aperture of the object side surface 41 of the fourth lens L4 to the intersection of the object side surface 41 of the fourth lens L4 and the optical axis O in the direction of the optical axis O (i.e., the sag height of the object side surface 41 of the fourth lens L4 at the maximum effective radius).

By limiting the ratio of the sagitta of the image side surface 22 of the second lens L2 at the maximum effective radius to the sagitta of the object side surface 41 of the fourth lens L4 at the maximum effective radius, the curvature of the second lens L2 and the fourth lens L4 can be limited, thereby balancing the large spherical aberration generated by the optical lens 100, promoting the aberration balance of the optical lens 100, and improving the overall resolution of the optical lens 100, thereby improving the imaging quality of the optical lens 100. At the same time, by controlling the sagitta of the second lens L2 and the fourth lens L4 at the maximum effective radius, it is beneficial to compress the size of the optical lens 100 to meet the miniaturization of the optical lens 100.

In some embodiments, the optical lens 100 satisfies the following relationship:

(|SAG41|+|SAG42|)/CT4<1;

Wherein, SAG41 is the distance from the maximum effective aperture of the object-side surface 41 of the fourth lens L4 to the intersection of the object-side surface 41 of the fourth lens L4 and the optical axis O in the direction of the optical axis O (i.e., the sagittal height of the object-side surface 41 of the fourth lens L4 at the maximum effective radius), SAG42 is the distance from the maximum effective aperture of the image-side surface 42 of the fourth lens L4 to the intersection of the image-side surface 42 of the fourth lens L4 and the optical axis O in the direction of the optical axis O (i.e., the sagittal height of the image-side surface 42 of the fourth lens L4 at the maximum effective radius), and CT4 is the thickness of the fourth lens L4 on the optical axis O (i.e., the central thickness of the fourth lens L4).

By constraining the above relationship, the refractive power and thickness of the fourth lens L4 can be reasonably controlled to avoid the fourth lens L4 being too thin or too thick, which is beneficial to maintaining a sufficiently small exit angle of the main light, thereby reducing the incident angle of the light on the imaging surface 101, thereby reducing the sensitivity of the optical lens 100 and improving the imaging quality of the optical lens 100.

In some embodiments, the optical lens 100 satisfies the following relationship:

1<|(R41-R42)/(R41+R42)|<1.5;

Wherein, R41 is the curvature radius of the object-side surface 41 of the fourth lens L4 at the optical axis O, and R42 is the curvature radius of the image-side surface 42 of the fourth lens L4 at the optical axis O.

By limiting the ratio of the curvature radii of the object-side surface 41 and the image-side surface 42 of the fourth lens L4, the curvature degree and thickness ratio trend of the object-side surface 41 and the image-side surface 42 of the fourth lens L4 can be effectively controlled to limit the shape change of the fourth lens L4. In this way, the spherical aberration contribution of the fourth lens L4 can be controlled within a reasonable range, thereby effectively improving the aberration of the optical lens 100 and enhancing the imaging quality of the optical lens 100. At the same time, it is also beneficial to reduce the surface complexity of the fourth lens L4 and improve the processability of the fourth lens L4, thereby ensuring the imaging quality of the optical lens 100.

In some embodiments, the optical lens 100 satisfies the following relationship:

|(R31-R32)/(R31+R32)|<0.5; and/or, 2<|f/f2+f/f4|<3;

Wherein, R31 is the curvature radius of the object side surface 31 of the third lens L3 at the optical axis O, R32 is the curvature radius of the image side surface 32 of the third lens L3 at the optical axis O, f is the focal length of the optical lens 100, f2 is the focal length of the second lens L2, and f4 is the focal length of the fourth lens L4.

By reasonably configuring the curvature radii of the object-side surface 31 and the image-side surface 32 of the third lens L3, the curvature of the third lens L3 can be effectively controlled, so that the lens shape of the third lens L3 is smooth and uniform, thereby reducing the assembly sensitivity of the optical lens 100. At the same time, the overall imaging quality from the center to the edge of the imaging surface 101 is clear and uniform, which can effectively reduce the risk of ghost images, enhance the resolution capability of the optical lens 100, and thus improve the imaging quality of the optical lens 100.

In addition, by properly configuring the focal length of the optical lens 100 and the focal lengths of the second lens L2 and the fourth lens L4, the large spherical aberration generated by the optical lens 100 can be balanced, the overall resolution of the optical lens 100 can be improved, and the edge aberration of the optical lens 100 can be corrected, thereby improving the imaging quality of the optical lens 100. At the same time, by controlling the focal length of the optical lens 100, the total length of the optical lens 100 can be compressed, thereby facilitating the miniaturization design of the optical lens 100.

In addition, the object side surface and the image side surface of any lens of the first lens L1 to the fourth lens L4 are both aspherical surfaces, and the surface shape of each aspherical lens can be defined by but not limited to the following aspherical surface formula:

Among them, Z is the distance from the corresponding point on the aspherical surface to the plane tangent to the vertex of the surface, r is the distance from any point on the aspherical surface to the optical axis, c is the curvature of the vertex of the aspherical surface, c = 1/Y, Y is the radius of curvature (that is, the paraxial curvature c is the reciprocal of the Y radius in Table 1), k is the cone constant, and Ai is the coefficient corresponding to the i-th high-order term in the aspherical surface shape formula.

The optical lens 100 of this embodiment will be described in detail below with reference to specific parameters.

First embodiment

The structural schematic diagram of the optical lens 100 disclosed in the first embodiment of the present application is shown in FIG1 , and the optical lens 100 includes a first lens L1, a stop STO, a second lens L2, a third lens L3, a fourth lens L4, and an infrared filter 50, which are sequentially arranged from the object side to the image side along the optical axis O. The materials of the first lens L1, the second lens L2, the third lens L3, and the fourth lens L4 can be referred to the above-mentioned specific embodiments, and will not be repeated here.

Furthermore, the first lens L1 has positive refractive power, the second lens L2 has positive refractive power, the third lens L3 has negative refractive power, and the fourth lens L4 has positive refractive power.

Furthermore, the object-side surface 11 and the image-side surface 12 of the first lens L1 are convex and concave respectively at the near optical axis O, the object-side surface 21 and the image-side surface 22 of the second lens L2 are both convex at the near optical axis O, the object-side surface 31 and the image-side surface 32 of the third lens L3 are respectively concave and convex at the near optical axis O, and the object-side surface 41 and the image-side surface 42 of the fourth lens L4 are both convex at the near optical axis O.

The object-side surface 11 and the image-side surface 12 of the first lens L1 are both convex surfaces at the circumference, the object-side surface 21 and the image-side surface 22 of the second lens L2 are respectively concave and convex surfaces at the circumference, the object-side surface 31 and the image-side surface 32 of the third lens L3 are respectively convex and concave surfaces at the circumference, and the object-side surface 41 and the image-side surface 42 of the fourth lens L4 are both convex surfaces at the circumference.

Specifically, taking the effective focal length f of the optical lens 100 = 3.11 mm, the aperture number Fno of the optical lens 100 = 2.0, the field of view FOV of the optical lens 100 = 70.0°, and the total length TTL of the optical lens 100 = 6.42 mm as an example, other parameters of the optical lens 100 are given in the following Table 1. Among them, the elements from the object side to the image side along the optical axis O of the optical lens 100 are arranged in the order of the elements from top to bottom in Table 1. In the same lens, the surface with a smaller surface number is the object side of the lens, and the surface with a larger surface number is the image side of the lens, such as surface numbers 1 and 2 correspond to the object side and image side of the first lens L1, respectively. The Y radius in Table 1 is the radius of curvature of the object side or image side of the corresponding surface number at the optical axis O. The first value in the "thickness" parameter column of the lens is the thickness of the lens on the optical axis O, and the second value is the distance from the image side of the lens to the next surface on the optical axis O. The value of the aperture STO in the "Thickness" parameter column is the distance from the aperture STO to the vertex of the next surface (the vertex refers to the intersection of the surface and the optical axis O) on the optical axis O. By default, the direction from the object side of the first lens L1 to the image side of the last lens is the positive direction of the optical axis O. When the value is negative, it indicates that the aperture STO is set on the image side of the next surface vertex. If the aperture STO thickness is a positive value, the aperture STO is on the object side of the next surface vertex. It can be understood that the units of the Y radius, thickness, and focal length in Table 1 are all mm, and the refractive index and Abbe number in Table 1 are obtained at a reference wavelength of 587.6nm, while the focal length is obtained at a reference wavelength of 555nm.

The k in Table 2 is a cone constant, and Table 2 gives the high-order coefficients A4, A6, A8, A10, A12, A14 and A16 that can be used for each aspherical mirror surface in the first embodiment.

Table 1

Table 2

Please refer to (A) in FIG. 2 , which shows the longitudinal spherical aberration curve of the optical lens 100 in the first embodiment at wavelengths of 650 nm, 610 nm, 555 nm, 510 nm and 470 nm. In (A) in FIG. 2 , the abscissa along the X-axis direction represents the focus offset in mm, and the ordinate along the Y-axis direction represents the normalized field of view. It can be seen from (A) in FIG. 2 that the spherical aberration value of the optical lens 100 in the first embodiment is better, indicating that the imaging quality of the optical lens 100 in this embodiment is better.

Please refer to (B) in FIG. 2 , which is a light astigmatism diagram of the optical lens 100 in the first embodiment at a wavelength of 555 nm. The horizontal axis along the X-axis direction represents the focus offset, and the vertical axis along the Y-axis direction represents the image height, in units of mm. T in the astigmatism curve represents the curvature of the imaging surface 101 in the meridian direction, and S represents the curvature of the imaging surface 101 in the sagittal direction. It can be seen from (B) in FIG. 2 that at this wavelength, the astigmatism of the optical lens 100 is well compensated.

Please refer to (C) in FIG. 2 , which is a distortion curve of the optical lens 100 in the first embodiment at a wavelength of 555 nm. The abscissa along the X-axis direction represents the distortion, and the ordinate along the Y-axis direction represents the image height, in units of mm. It can be seen from (C) in FIG. 2 that at this wavelength, the distortion of the optical lens 100 is well corrected.

Second embodiment

The structural schematic diagram of the optical lens 100 disclosed in the second embodiment of the present application is shown in FIG3 , and the optical lens 100 includes a first lens L1, a stop STO, a second lens L2, a third lens L3, a fourth lens L4, and an infrared filter 50, which are sequentially arranged from the object side to the image side along the optical axis O. The materials of the first lens L1, the second lens L2, the third lens L3, and the fourth lens L4 can be referred to the description in the above specific implementation manner, and will not be repeated here.

Furthermore, the first lens L1 has negative refractive power, the second lens L2 has positive refractive power, the third lens L3 has negative refractive power, and the fourth lens L4 has positive refractive power.

Furthermore, the object-side surface 11 and the image-side surface 12 of the first lens L1 are convex and concave respectively at the near optical axis O, the object-side surface 21 and the image-side surface 22 of the second lens L2 are concave and convex respectively at the near optical axis O, the object-side surface 31 and the image-side surface 32 of the third lens L3 are concave and convex respectively at the near optical axis O, and the object-side surface 41 and the image-side surface 42 of the fourth lens L4 are both convex at the near optical axis O.

The object-side surface 11 and the image-side surface 12 of the first lens L1 are convex and concave surfaces respectively at the circumference, the object-side surface 21 and the image-side surface 22 of the second lens L2 are concave and convex surfaces respectively at the circumference, the object-side surface 31 and the image-side surface 32 of the third lens L3 are convex and concave surfaces respectively at the circumference, and the object-side surface 41 and the image-side surface 42 of the fourth lens L4 are both convex surfaces at the circumference.

Specifically, take the effective focal length f of the optical lens 100 = 3.0 mm, the aperture number Fno of the optical lens 100 = 2.0, the field of view FOV of the optical lens 100 = 71.7°, and the total length TTL of the optical lens 100 = 7.07 mm as an example.

Other parameters in the second embodiment are given in the following Table 3, and the definitions of the parameters can be obtained from the description of the above embodiments, and are not repeated here. It can be understood that the units of the Y radius, thickness, and focal length in Table 3 are all mm, and the refractive index and Abbe number in Table 3 are obtained at a reference wavelength of 587.6 nm, while the focal length is obtained at a reference wavelength of 555 nm.

The k in Table 4 is a cone constant, and Table 4 gives the high-order coefficients A4, A6, A8, A10, A12, A14 and A16 that can be used for each aspherical mirror surface in the second embodiment.

Table 3

Table 4

Please refer to FIG. 4 . It can be seen from the light spherical aberration curve (A) in FIG. 4 , the light astigmatism curve (B) in FIG. 4 , and the distortion curve (C) in FIG. 4 that the longitudinal spherical aberration, astigmatism, and distortion of the optical lens 100 are well controlled, so that the optical lens 100 of this embodiment has good imaging quality. In addition, the wavelengths corresponding to the curves in FIG. 4 (A), FIG. 4 (B), and FIG. 4 (C) can refer to the contents described in FIG. 2 (A), FIG. 2 (B), and FIG. 2 (C) in the first embodiment, and will not be repeated here.

Third embodiment

The structural schematic diagram of the optical lens 100 disclosed in the third embodiment of the present application is shown in FIG5 , and the optical lens 100 includes a first lens L1, a stop STO, a second lens L2, a third lens L3, a fourth lens L4, and an infrared filter 50, which are sequentially arranged from the object side to the image side along the optical axis O. The materials of the first lens L1, the second lens L2, the third lens L3, and the fourth lens L4 can be referred to the description in the above specific implementation manner, and will not be repeated here.

Furthermore, the first lens L1 has positive refractive power, the second lens L2 has positive refractive power, the third lens L3 has negative refractive power, and the fourth lens L4 has positive refractive power.

Furthermore, the object-side surface 11 and the image-side surface 12 of the first lens L1 are convex and concave respectively at the near optical axis O, the object-side surface 21 and the image-side surface 22 of the second lens L2 are both convex at the near optical axis O, the object-side surface 31 and the image-side surface 32 of the third lens L3 are respectively concave and convex at the near optical axis O, and the object-side surface 41 and the image-side surface 42 of the fourth lens L4 are both convex at the near optical axis O.

The object-side surface 11 and the image-side surface 12 of the first lens L1 are convex and concave surfaces respectively at the circumference, the object-side surface 21 and the image-side surface 22 of the second lens L2 are concave and convex surfaces respectively at the circumference, the object-side surface 31 and the image-side surface 32 of the third lens L3 are convex and concave surfaces respectively at the circumference, and the object-side surface 41 and the image-side surface 42 of the fourth lens L4 are both convex surfaces at the circumference.

Specifically, take the effective focal length f of the optical lens 100 = 3.09 mm, the aperture number Fno of the optical lens 100 = 1.80, the field of view FOV of the optical lens 100 = 69.8°, and the total length TTL of the optical lens 100 = 6.43 mm as an example.

Other parameters in the third embodiment are given in the following Table 5, and the definitions of the parameters can be obtained from the description of the previous embodiment, and are not repeated here. It can be understood that the units of the Y radius, thickness, and focal length in Table 5 are all mm, and the refractive index and Abbe number in Table 5 are obtained at a reference wavelength of 587.6nm, while the focal length is obtained at a reference wavelength of 555nm.

The k in Table 6 is a cone constant, and Table 6 gives the high-order coefficients A4, A6, A8, A10, A12, A14 and A16 that can be used for each aspherical mirror surface in the third embodiment.

Table 5

Table 6

Please refer to FIG6 . It can be seen from the light spherical aberration curve (A) in FIG6 , the light astigmatism curve (B) in FIG6 , and the distortion curve (C) in FIG6 that the longitudinal spherical aberration, astigmatism, and distortion of the optical lens 100 are well controlled, so that the optical lens 100 of this embodiment has good imaging quality. In addition, the wavelengths corresponding to the curves in FIG6 (A), FIG6 (B), and FIG6 (C) can refer to the contents described in FIG2 (A), FIG2 (B), and FIG2 (C) in the first embodiment, which will not be repeated here.

Fourth embodiment

The structural schematic diagram of the optical lens 100 disclosed in the fourth embodiment of the present application is shown in FIG7 , and the optical lens 100 includes a first lens L1, a stop STO, a second lens L2, a third lens L3, a fourth lens L4, and an infrared filter 50, which are sequentially arranged from the object side to the image side along the optical axis O. The materials of the first lens L1, the second lens L2, the third lens L3, and the fourth lens L4 can be referred to the description in the above specific implementation manner, and will not be repeated here.

Furthermore, the first lens L1 has positive refractive power, the second lens L2 has positive refractive power, the third lens L3 has negative refractive power, and the fourth lens L4 has positive refractive power.

Furthermore, the object-side surface 11 and the image-side surface 12 of the first lens L1 are convex and concave respectively at the near optical axis O, the object-side surface 21 and the image-side surface 22 of the second lens L2 are both convex at the near optical axis O, the object-side surface 31 and the image-side surface 32 of the third lens L3 are concave and convex respectively at the near optical axis O, and the object-side surface 41 and the image-side surface 42 of the fourth lens L4 are convex and concave respectively at the near optical axis O.

The object-side surface 11 and the image-side surface 12 of the first lens L1 are convex and concave surfaces respectively at the circumference, the object-side surface 21 and the image-side surface 22 of the second lens L2 are concave and convex surfaces respectively at the circumference, the object-side surface 31 and the image-side surface 32 of the third lens L3 are convex and concave surfaces respectively at the circumference, and the object-side surface 41 and the image-side surface 42 of the fourth lens L4 are both convex surfaces at the circumference.

Specifically, take the effective focal length f of the optical lens 100 = 3.09 mm, the aperture number Fno of the optical lens 100 = 1.69, the field of view FOV of the optical lens 100 = 69.9°, and the total length TTL of the optical lens 100 = 6.40 mm as an example.

Other parameters in the fourth embodiment are given in the following Table 7, and the definitions of the parameters can be obtained from the description of the previous embodiment, and are not repeated here. It can be understood that the units of the Y radius, thickness, and focal length in Table 7 are all mm, and the refractive index and Abbe number in Table 7 are obtained at a reference wavelength of 587.6nm, while the focal length is obtained at a reference wavelength of 555nm.

The k in Table 8 is a cone constant, and Table 8 gives the high-order coefficients A4, A6, A8, A10, A12, A14 and A16 that can be used for each aspherical mirror surface in the fourth embodiment.

Table 7

Table 8

Please refer to FIG8 . It can be seen from the light spherical aberration curve (A) in FIG8 , the light astigmatism curve (B) in FIG8 , and the distortion curve (C) in FIG8 that the longitudinal spherical aberration, astigmatism, and distortion of the optical lens 100 are well controlled, so that the optical lens 100 of this embodiment has good imaging quality. In addition, the wavelengths corresponding to the curves in FIG8 (A), FIG8 (B), and FIG8 (C) can refer to the contents described in FIG2 (A), FIG2 (B), and FIG2 (C) in the first embodiment, which will not be repeated here.

Fifth embodiment

The structural schematic diagram of the optical lens 100 disclosed in the fifth embodiment of the present application is shown in FIG9 , and the optical lens 100 includes a first lens L1, a stop STO, a second lens L2, a third lens L3, a fourth lens L4, and an infrared filter 50, which are sequentially arranged from the object side to the image side along the optical axis O. The materials of the first lens L1, the second lens L2, the third lens L3, and the fourth lens L4 can be referred to the above-mentioned specific embodiments, and will not be repeated here.

Furthermore, the first lens L1 has positive refractive power, the second lens L2 has positive refractive power, the third lens L3 has negative refractive power, and the fourth lens L4 has positive refractive power.

Furthermore, the object-side surface 11 and the image-side surface 12 of the first lens L1 are convex and concave respectively at the near optical axis O, the object-side surface 21 and the image-side surface 22 of the second lens L2 are both convex at the near optical axis O, the object-side surface 31 and the image-side surface 32 of the third lens L3 are respectively concave and convex at the near optical axis O, and the object-side surface 41 and the image-side surface 42 of the fourth lens L4 are both convex at the near optical axis O.

The object-side surface 11 and the image-side surface 12 of the first lens L1 are both convex surfaces at the circumference, the object-side surface 21 and the image-side surface 22 of the second lens L2 are respectively concave and convex surfaces at the circumference, the object-side surface 31 and the image-side surface 32 of the third lens L3 are respectively convex and concave surfaces at the circumference, and the object-side surface 41 and the image-side surface 42 of the fourth lens L4 are both convex surfaces at the circumference.

Specifically, take the effective focal length f of the optical lens 100 = 3.0 mm, the aperture number Fno of the optical lens 100 = 1.8, the field of view FOV of the optical lens 100 = 71.3°, and the total length TTL of the optical lens 100 = 7.0 mm as an example.

Other parameters in the fifth embodiment are given in the following Table 9, and the definitions of the parameters can be obtained from the description of the previous embodiment, and are not repeated here. It can be understood that the units of the Y radius, thickness, and focal length in Table 9 are all mm, and the refractive index and Abbe number in Table 9 are obtained at a reference wavelength of 587.6nm, while the focal length is obtained at a reference wavelength of 555nm.

The k in Table 10 is a cone constant, and Table 10 gives the high-order coefficients A4, A6, A8, A10, A12, A14 and A16 that can be used for each aspherical mirror surface in the fifth embodiment.

Table 9

Table 10

Please refer to FIG. 10 . It can be seen from the light spherical aberration curve (A) in FIG. 10 , the light astigmatism curve (B) in FIG. 10 , and the distortion curve (C) in FIG. 10 that the longitudinal spherical aberration, astigmatism, and distortion of the optical lens 100 are well controlled, so that the optical lens 100 of this embodiment has good imaging quality. In addition, the wavelengths corresponding to the curves in FIG. 10 (A), FIG. 10 (B), and FIG. 10 (C) can refer to the contents described in FIG. 2 (A), FIG. 2 (B), and FIG. 2 (C) in the first embodiment, which will not be repeated here.

Please refer to Table 11, which is a summary of the ratios of various relationship equations in the first to fifth embodiments of the present application.

Table 11

Please refer to Figure 11. The present application also discloses a camera module 200, which includes an image sensor 201 and an optical lens 100 as described in any one of the first to fifth embodiments above, and the image sensor 201 is arranged on the image side of the optical lens 100. The optical lens 100 is used to receive the light signal of the subject and project it to the image sensor 201. The image sensor 201 is used to convert the light signal corresponding to the subject into an image signal, which will not be described in detail here. It can be understood that the camera module 200 with the above optical lens 100 can achieve high imaging quality while meeting the design requirements of miniaturization. Since the above technical effects have been described in detail in the embodiment of the optical lens 100, they will not be described in detail here.

Please refer to Figure 12. The present application also discloses an electronic device 300, which includes a housing 301 and the above-mentioned camera module 200, and the camera module 200 is arranged in the housing 301. Among them, the electronic device 300 can be but not limited to a mobile phone, a tablet computer, a laptop computer, a smart watch, a monitor, a driving recorder, a reversing image, etc. It can be understood that the electronic device 300 with the above-mentioned camera module 200 also has all the technical effects of the above-mentioned optical lens. That is, while achieving high imaging quality, it can also meet the design requirements of miniaturization. Since the above-mentioned technical effects have been described in detail in the embodiment of the optical lens, they will not be repeated here.

The optical lens, camera module and electronic device disclosed in the embodiments of the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the optical lens, camera module and electronic device of the present invention and their core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims (7)

1. an optical lens, is characterized in that, shares four lenses with refractive power, and described optical lens comprises successively from object side to image side along optical axis: The first lens has refractive power, the object side of the first lens is convex at the near optical axis, and the image side of the first lens is concave at the near optical axis; The second lens has positive refractive power, and the image side of the second lens is convex at the near optical axis; The third lens has a negative refractive power, the object side of the third lens is concave at the near optical axis, and the image side of the third lens is convex at the near optical axis; The fourth lens has positive refractive power, the object side of the fourth lens is convex at the near optical axis, and the first to fourth lenses include at least one aspherical lens; The optical lens satisfies the relational expression: 3<|f2/SAG22|<6; 0.404≤(|SAG41|+|SAG42|)/CT4≤0.82; 0.432≤|SAG22/SAG41|<1.2; Wherein, f2 is the focal length of the second lens, and SAG22 is the intersection point from the maximum effective aperture of the image side of the second lens to the image side of the second lens and the optical axis in the direction of the optical axis SAG41 is the distance from the maximum effective aperture of the object side of the fourth lens to the intersection of the object side of the fourth lens and the optical axis in the direction of the optical axis, and SAG42 is the distance of the fourth lens The distance from the maximum effective aperture of the image side of the lens to the intersection of the image side of the fourth lens and the optical axis in the direction of the optical axis, CT4 is the thickness of the fourth lens on the optical axis . 2. optical lens according to claim 1, is characterized in that, described optical lens satisfies relational expression: 0.4<|f12/f34|<0.8; Wherein, f12 is the combined focal length of the first lens and the second lens, and f34 is the combined focal length of the third lens and the fourth lens. 3. optical lens according to claim 1, is characterized in that, described optical lens satisfies relational expression: 1<|f4/SAG41|<3; Wherein, f4 is the focal length of the fourth lens, SAG41 is the maximum effective aperture of the object side of the fourth lens to the intersection of the object side of the fourth lens and the optical axis in the direction of the optical axis distance. 4. optical lens according to claim 1, is characterized in that, described optical lens satisfies relational expression: 1<|(R41-R42)/(R41+R42)|<1.5; Wherein, R41 is the radius of curvature of the object side of the fourth lens at the optical axis, and R42 is the radius of curvature of the image side of the fourth lens at the optical axis. 5. optical lens according to claim 1, is characterized in that, described optical lens satisfies relational expression: |(R31-R32)/(R31+R32)|<0.5; and/or, 2<|f/f2+f/f4|<3; Wherein, R31 is the radius of curvature of the object side of the third lens at the optical axis, R32 is the radius of curvature of the image side of the third lens at the optical axis, and f is the focal length of the optical lens , f2 is the focal length of the second lens, and f4 is the focal length of the fourth lens. 6. A camera module, characterized in that the camera module comprises an image sensor and the optical lens according to any one of claims 1-5, and the image sensor is arranged on the image side of the optical lens. 7. An electronic device, characterized in that: the electronic device comprises a housing and the camera module according to claim 6, the camera module is arranged on the housing.